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Your logic is extremely flawed. The whole point of the dual mass flywheel and cdv is for smoother shifts...

Sent from my DROIDX using Bimmer App

wrong. CDV is to prevent damage to the drivetrain from aggressive driving. here's a quote from the Zeckhausen website:

Quote:

The Clutch Delay Valve (CDV) is a one-way restrictor installed by the factory between the clutch slave cylinder and clutch master cylinder, as shown in Figure 1. It "delays" the engagement of the clutch, much like old record players use a damped tone-arm to gently lower the needle onto the surface of a record.

Because of this valve, no matter how quickly you lift your foot off the clutch pedal, the clutch engages the flywheel at a constant (slow) rate. In theory, it can save the driveline from shock, were an inexperienced (or immature) driver to dump the clutch. But in practice, all it does is prematurely wear out the clutch and turn experienced drivers into people who, despite years of practice, cannot shift smoothly.

I don't know who these people are who "cannot shift smoothly". We left the CDV in place on my girlfriend's 330Ci, and we both shift as smooth as glass, in spite of the fact that we've both been driving manual transmissions for over 40 years. A clunky shift on these cars is either pilot error, or there's something mechanically wrong, such as a worn throw-out bearing. Our 103,000 miles with the CDV in place show that the CDV doesn't cause rough shifting.

Edit: And the original clutch is still in the car, so it's not exactly worn out prematurely. By the way, I'm a (relatively) conservative driver, but she's not - she drives like a bat out of hell. I have to work at it to keep up in my 545.

And how am I wrong? It prevents sudden clutch releases, aka, smoother shifting... It's like all modern BMW Inovations that assume the driver of the car is a nitwit, sadly they're probably right about most drivers.

I don't know who these people are who "cannot shift smoothly". We left the CDV in place on my girlfriend's 330Ci, and we both shift as smooth as glass, in spite of the fact that we've both been driving manual transmissions for over 40 years. A clunky shift on these cars is either pilot error, or there's something mechanically wrong, such as a worn throw-out bearing. Our 103,000 miles with the CDV in place show that the CDV doesn't cause rough shifting.

Edit: And the original clutch is still in the car, so it's not exactly worn out prematurely. By the way, I'm a (relatively) conservative driver, but she's not - she drives like a bat out of hell. I have to work at it to keep up in my 545.

Shifting speed/techique is a big part of this. I shift too fast apparently. CDV valve was acting like it was a shift gate. Removed it and don't have that problem anymore. I drove it 10k+ miles before I finally removed it. Problem gone.

And how am I wrong? It prevents sudden clutch releases, aka, smoother shifting... It's like all modern BMW Inovations that assume the driver of the car is a nitwit, sadly they're probably right about most drivers.

Again, how am I wrong? CDV DELAYS THE CLUTCH. It's so that you don't drop the clutch and chirp your tires (SMOOTHER SHIFTING). I didn't say he was wrong about it preventing drivetrain wear, but it also allows smoother shifting for those who fail at driving a clutch, so please kindly eatadik

Well the downside is that you can smoke your fly wheel/clutch in no time if you have a few bad shifts.

but the problem may be else where

Only if you're a dumb f****er. People have been driving without CDVs for a long time. God knows why BMW thought it was a good thing to intervene between a driver and their foot in the first place. Its a lot more flexible than a ferkin CDV. Makes no sense to me at all. I think they did it to mask a crappy diaphragm design.

Hi
I am new to BMW's. I have read a few posts on here when I have been searching for information on clutch delay valves. I have a 2001 320i and cannot get a smooth gear change. I have been driving for 30 years so feel like a learner when the car jerks on gear changes. I have read that most people have removed the valve but just wondered if there were any negatives by doing this. Would it solve one problem and create another.
Any info would be most appreciated.

Just do it. If you can use a clutch then there's no problem. It will be similar to the vid below

I don't know who these people are who "cannot shift smoothly". We left the CDV in place on my girlfriend's 330Ci, and we both shift as smooth as glass, in spite of the fact that we've both been driving manual transmissions for over 40 years. A clunky shift on these cars is either pilot error, or there's something mechanically wrong, such as a worn throw-out bearing. Our 103,000 miles with the CDV in place show that the CDV doesn't cause rough shifting.

Congratulations! You've been enjoying smooth shifts for all those miles in your 330Ci coupe because you never had a CDV. Not installed on this model.

I think the coupe is just designed with more spirited driving in mind and things are slanted in that direction. Comes standard with sport suspension, etc.
The rest of the breed is more of a compromise with lux smooth driving.

Even normal daily driving you'll notice the difference. I always fell like a jackass jerking the car around. Finally removed it and wow. Why did i wait so long.
Some say you can do more damage to the drive train with it removed, other say it causes trouble.

There were two things that disappointing me when i got my 330. The shifting was.. meh.. and the throttle response was slow. Removing the cdv fixed most of the shifting issues. Maybe a chip will fix the throttle response.

At this point I think we've extended ourselves into the rarefied and arcane world of what minutiae options did BMW fiddle with in various markets around the world. I'm not up for joining the nerd club, so I'll politely disengage thank you.
My concern is only with the USA.